TagTinker Lets You Hack Electronic Shelf Labels

May 4, 2026 by 10 Comments

Was there ever anything wrong with simple paper price labels? Absolutely not. And yet, the world invented the electronic price tag anyway. If you happen to come across some of these devices and want to hack them, you might like TagTinker from [i12bp8].

TagTinker is a Flipper Zero application specifically built for talking to infrared electronic shelf labels (ESLs). These are e-paper devices that receive commands and updates via an infrared interface, and they’re relatively simple to talk to. [i12bp8] built upon previous work from [furrtek] which revealed the protocols used to update these devices, and implemented it into an app that runs on the Flipper. It can do neat things like scan the NFC tags built into ESLs to ID them, deploy bitmap images to the tags, or run live-updated dashboards on the devices with the aid of a Flipper WiFi devboard.

If you’ve always wanted to play with these tags but didn’t want to do the grunt work yourself, it just got a whole lot easier to mess around. Though, it’s worth noting, [i12bp8] has strictly prohibited any illegal uses of this app, so be good out there. We’ve seen these tags repurposed before, too – who knew they could make such good conference badges? 

TDR For Auto Diagnostics Done On The Cheap

May 4, 2026 by 6 Comments

A time domain reflectometer (TDR) is a useful tool to have for finding faults in a wiring harness. However, they don’t come cheap, putting them out of reach for many shadetree mechanics that like to work on their own cars. However, [László SZŐKE] has been exploring a neat way to build a similar device on the cheap.

Typically, time domain reflectometry involves shooting a short electric pulse down a wire, and listening for how long it takes to bounce back. The time depends on the length of the wire, so it can be used to determine the location of a break in conductivity. Unfortunately, these pulses move so fast that very fast, very expensive hardware is needed to make these measurements.

[László’s] technique relies on lower-tech hardware. Instead of sending a very short pulse down a wire, his rig uses a cheap C-Media USB audio device to send a 4 kHz or 8 kHz sine wave instead. Then, by listening to the reflection and measuring the phase shift, it’s possible to detect the distance to the end of the wire (or a break along its length). Some supporting hardware is required for protection’s sake, and to tune the setup for measuring shorter or longer cabling. However, with some smart software processing, [László] states that it’s possible to measure down to 1 cm resolution.

The idea is that this setup could prove particularly useful for automotive troubleshooting. If you measure a wire and the device reports a length of 30 cm, when you know the wire stretches several meters into the engine bay… you know there’s a break around 30 cm from your measurement point.

There’s still plenty of work to be done – for now, [László] is working on a new prototype that should have better performance when testing shorter cables. Still, we love to see this sort of out-of-the-box thinking put towards a common troubleshooting task. If you’re doing fun signal analysis work of your own, don’t hesitate to light up the tipsline.

A man's hand is shown holding a color photograph of a vase of flowers against a black background.

True-Spectrum Photography With Structural Color

May 3, 2026 by 10 Comments

Although modern cameras can, with skill and good conditions, produce photographs nearly indistinguishable from the original scene, this fidelity relies on the limitations of human vision. According to the trichromatic theory, humans perceive light as a mixture of three colors, which can be recorded and represented by cameras, displays, and color printing; a spectrometer, however, can detect a clear distance between the three colors present in a photograph and the wide range of spectra in the original scene. By contrast, one of the earliest color photography methods, Lippmann plates, captured not just true color, but true spectra.

A Lippmann plate, as [Jon Hilty] details, starts with a layer of photographic gel containing extremely fine silver halide crystals over the back of a glass plate. This layer is placed on top of a mirror, traditionally a mercury bath, and put in the camera. When light passes through the emulsion and reflects off the mirror, it interferes with incoming light to create a standing wave. The portions of the emulsion at the wave’s antinodes absorb the most energy, converting local silver halide crystals into reflective silver. The spacing of the silver particles depends on the incoming light’s wavelength, and is fixed in place during the development process.

This creates a matrix of vertically-stacked diffraction gratings, each diffracting back the original wavelength when illuminated with white light. Unlike normal diffraction gratings, the wavelength of diffracted light doesn’t depend strongly on the viewing angle; since the interference structure here is vertically-arranged, it refracts a narrow range of wavelengths across all possible viewing angles. The viewing angles, however, are limited; unlike with dye-based photographs, you can only view the colors nearly straight-on. This, along with the necessity for long exposures, the chance of producing washed-out colors, and the impossibility of creating reprints, kept Lippmann plates from ever really catching on. The basic concept lives on in holograms, which encode spatial information in a similar kind of photographically-formed diffraction pattern.

For a more conventional method of color photography, we’ve also seen a recreation of the autochrome method. Alternatively, check out this homemade silver halide photography emulsion.

Thanks to [Stephen Walters] for the tip!

ReactOS Gets Unified Installer Image And A New Storage Stack

May 3, 2026 by 6 Comments

Although the ReactOS project is in no rush to dethrone Windows as the desktop operating system of choice, this doesn’t mean that some real changes aren’t happening. Most recently two big changes got merged, the first pertaining to the separate boot- and live CD images that are now merged into a single image, and the second being a new PnP-aware ATA storage stack for ATA and AHCI devices, with NT6+ compatibility.

Although there is still a separate live CD for now, this first change means that testing and installing ReactOS becomes easier, and that the old-school text-based installer may soon be on its way out as well.

Having the new ATA storage stack in place will translate into much better compatibility with real hardware, including the ability to use more hardware to install on and boot from compared to the old UniATA driver.

Combined, these two changes should bring the ReactOS installation and usage experience a lot closer to that of Windows, as well as many Linux distros. If you had issues with the OS on real hardware, this might be just the right time to give it another shake and provide detailed feedback to the developers if any remaining issues are encountered.

Thanks to [jeditobe] for the tip.

Hackaday Links Column Banner

Hackaday Links: May 3, 2026

May 3, 2026 by 3 Comments

Software that collects public data from the Internet and uses it to provide half-assed answers to your questions might seem like a modern craze, but today we bid farewell to a website that helped pioneer pretend conversations all the way back in 1997 — as of May 1st, Ask Jeeves is no more.

Well, technically they dropped the “Jeeves” part back in 2006. Since then it’s just been Ask.com, but as the name implies the idea was more or less the same. Rather than the relatively rigid parameters and keywords required by traditional search engines, you could ask Jeeves questions about the world using natural language. Early advertisements showed the virtual valet answering arbitrary questions like “How many calories in a banana?,” which of course today seems commonplace and utterly unimpressive, but was a pretty wild for the 1990s.

It might seem surprising that a site designed from day one to offer a human-like Q&A experience should fold right as such technology is becoming commonplace. But of course, that commonality is the problem. When Google can answer your questions just as well (or poorly…) as Jeeves or anyone else, what’s the benefit for the average Internet user to seek out another service? But it’s still somewhat ironic, which is probably why the farewell message on Ask.com ends with the line “Jeeves’ spirit endures.”

Continue reading “Hackaday Links: May 3, 2026” →

IPod Nano Gets Three Monitors

May 3, 2026 by 5 Comments

Triple monitor workstations are pretty common these days, particularly for those wishing to maximise screen space for greater productivity. [Will It Work?] has put together a sillier take on this concept, however, hooking the diminutive iPod Nano up to three monitors instead.

The 6th-generation iPod nano brought forth a new form factor – it’s the postage stamp-sized one that you could clip to your workout gear. It’s not typically what you’d call a productivity device, but there is a way to get more out of it. The trick is to grab a 30-pin Keyboard Dock, which allows access to the composite video signal from the iPod. It was originally designed for the iPad, but it works with the iPad nano too with a 30-pin spacer adapter – just don’t expect the keys to do anything. This setup also allows access to the 3.5mm four-pole jack, which handles audio input and output. With a bunch of additional cables and adapters, the iPod was able to be hooked up to three screens, a set of Apple Pro speakers, and three Sharp LCD monitors.

What can you do with this setup? Fundamentally, not a whole lot. You can’t use the keyboard with the iPod Nano, so you’re limited to interacting with the tiny touchscreen. There also aren’t exactly a lot of apps to run on the platform, either. You can basically listen to music, watch a slide show, or record voice memos, while looking at the iPod’s display spread identically across three TVs. Still, it’s a fun joke build, because at a glance it genuinely looks like you’ve set up a triple-monitor workstation running off a tiny iPod from over a decade ago.

If you want to blow the mind of your next podcast guest, consider recording your next episode on this rig. Alternatively, explore some of the other hacks we’ve seen for the platform. Video after the break.

Continue reading “IPod Nano Gets Three Monitors” →

Three-Axis Camera Slider From 3D Printer Parts

May 3, 2026 by 3 Comments

There’s a great reason 3D printers are made with things like extruded aluminum rails and other commodity, off-the-shelf parts. These things are designed not only for ease of construction and prototyping, but they’re also fairly strong especially given how modular they are. And they are excellent platforms for other projects as well. [CNCDan] has been using plenty of on-hand 3D printer parts to build a three-axis camera slider to film parts of his other projects, and this video documents his build and the latest upgrades to this platform.

After sorting out some issues with underpowered motors by improving their gear ratios, he found that many of the sizes and clearances on the existing platform changed enough that he needed to redo other parts of the carrier, including the mounting plate. He cut a new plate from steel and pressed bearings in, and then started putting together the other axes including a quick release mechanism for his camera. With a camera that weighs about 1.4 kg, getting the motors to move the camera smoothly was its own challenge. He re-worked all of his driver code over the course of a few weeks and eventually got his new system working much better than the original version.

With everything said and done, the camera slider can be controlled wirelessly with a GUI on another computer. Everything runs on an ESP32, and the slider can support other cameras besides his heavier one, including smartphones. He notes that this wasn’t the easiest way to build a project like this, but worked for him eventually because he had the parts and tools on hand to make it work. He’s also put the project files up on a GitHub page for anyone interested. Camera sliders like these have some niche uses as well; take a look at this high-speed camera slider for some examples.

Continue reading “Three-Axis Camera Slider From 3D Printer Parts” →